VBI Vaccines has reported preliminary data from Phase I part of its Phase I/II clinical trial where its Covid-19 vaccine candidate, VBI-2902a, induced potent immune responses in healthy adult subjects.

A monovalent and enveloped virus-like particle (eVLP) Covid-19-specific vaccine, VBI-2902 expresses the SARS-CoV-2 spike protein. It is adjuvanted with aluminium phosphate to form VBI-2902a.

The adaptive, randomised, observer-blind, placebo-controlled Phase I/II trial is currently underway.

The Phase I part analysed 5µg VBI-2902a in one-dose and two-dose vaccination regimens, with the second dose being administrated after 28 days.

Phase I enrolled 61 healthy, unvaccinated adults aged 18 to 54 years.

Data showed that the 5µg dose was well-tolerated and induced robust immune responses, which were greater than those observed in human convalescent sera.

No safety signals linked to the vaccine were noted and the safety profile was in line with that reported in previous eVLP clinical trials.

Furthermore, two doses of VBI-2902a elicited neutralisation titers and stimulated antibody binding titers in all the trial subjects.

In a statement, VBI Vaccines said: “The data establish a robust human proof-of-concept, at a low dose without the use of a next-generation adjuvant, demonstrating the potency of the eVLP particulate delivery platform against Covid-19.”

These results also support the evaluation of a one-dose booster regimen in seropositive people.

VBI Vaccines president and CEO Jeff Baxter said: “We are encouraged by the validating data seen to-date from VBI-2902a, one of several eVLP candidates we are developing to target known and emerging variants of Covid-19, with the partnership and support of the Government of Canada, CEPI, and The National Research Council of Canada.”

In the third quarter of this year, VBI Vaccines intends to commence the next phase of the Phase I/II trial to evaluate one and two doses of VBI-2905a in seropositive and seronegative individuals, respectively.

VBI-2905a is the company’s eVLP candidate that expresses the spike protein of the Beta or B.1.351 Covid-19 variant.

In the first half of next year, VBI will begin the first clinical trial of its multivalent candidate, which can boost the extent of protection provided against Covid-19.